(1)

Reserved.

(2)

Where contaminants of concern are present in the outdoor air of the local area of the building site, ventilation required by Sentence 6.3.1.1.(1) shall be provided by a ventilation system designed to include devices that reduce the concentrations of contaminants to those permitted in the ACGIH’s “Industrial Ventilation: A Manual of Recommended Practice for Design” prior to the introduction of outdoor air to indoor occupied spaces.